function utf8_decode(str_data){
	
	var tmp_arr = [], i = 0, ac = 0, c1 = 0, c2 = 0, c3 = 0;

	str_data += '';

	while(i < str_data.length){
		c1 = str_data.charCodeAt(i);
		if(c1 < 128){
			tmp_arr[ac++] = String.fromCharCode(c1);
			i++;
		} else if ((c1 > 191) && (c1 < 224)){
			c2 = str_data.charCodeAt(i + 1);
			tmp_arr[ac++] = String.fromCharCode(((c1 & 31) << 6) | (c2 & 63));
			i += 2;
		} else {
			c2 = str_data.charCodeAt(i + 1);
			c3 = str_data.charCodeAt(i + 2);
			tmp_arr[ac++] = String.fromCharCode(((c1 & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
			i += 3;
		}
	}

	return tmp_arr.join('');
}

function unserialize(data){	
	var that = this;
	var utf8Overhead = function(chr){
		// http://phpjs.org/functions/unserialize:571#comment_95906
		var code = chr.charCodeAt(0);
		if(code < 0x0080){
			return 0;
		}
		if(code < 0x0800){
			return 1;
		}
		return 2;
	};

	var error = function (type, msg, filename, line){throw new that.window[type](msg, filename, line);};
	var read_until = function(data, offset, stopchr){
		var buf = [];
		var chr = data.slice(offset, offset + 1);
		var i = 2;
		while(chr != stopchr){
			if((i + offset) > data.length){
				error('Error', 'Invalid');
			}
			buf.push(chr);
			chr = data.slice(offset + (i - 1),offset + i);
			i += 1;
		}
		return [buf.length, buf.join('')];
	};
	var read_chrs = function (data, offset, length){
		var buf;

		buf = [];
		for(var i = 0; i < length; i++){
			var chr = data.slice(offset + (i - 1), offset + i);
			buf.push(chr);
			length -= utf8Overhead(chr);
		}
		return [buf.length, buf.join('')];
	};
	var _unserialize = function(data, offset){
		var readdata;
		var readData;
		var chrs = 0;
		var ccount;
		var stringlength;
		var keyandchrs;
		var keys;

		if(!offset){ offset = 0; }
		var dtype = (data.slice(offset, offset + 1)).toLowerCase();

		var dataoffset = offset + 2;
		var typeconvert = function(x) {return x;};

		switch(dtype){
			case 'i':
				typeconvert = function (x) {return parseInt(x, 10);};
				readData = read_until(data, dataoffset, ';');
				chrs = readData[0];
				readdata = readData[1];
				dataoffset += chrs + 1;
				break;
			case 'b':
				typeconvert = function (x) {return parseInt(x, 10) !== 0;};
				readData = read_until(data, dataoffset, ';');
				chrs = readData[0];
				readdata = readData[1];
				dataoffset += chrs + 1;
				break;
			case 'd':
				typeconvert = function (x) {return parseFloat(x);};
				readData = read_until(data, dataoffset, ';');
				chrs = readData[0];
				readdata = readData[1];
				dataoffset += chrs + 1;
				break;
			case 'n':
				readdata = null;
				break;
			case 's':
				ccount = read_until(data, dataoffset, ':');
				chrs = ccount[0];
				stringlength = ccount[1];
				dataoffset += chrs + 2;

				readData = read_chrs(data, dataoffset+1, parseInt(stringlength, 10));
				chrs = readData[0];
				readdata = readData[1];
				dataoffset += chrs + 2;
				if(chrs != parseInt(stringlength, 10) && chrs != readdata.length){
					error('SyntaxError', 'String length mismatch');
				}

				// Length was calculated on an utf-8 encoded string
				// so wait with decoding
				//readdata = that.utf8_decode(readdata);
				break;
			case 'a':
				readdata = {};

				keyandchrs = read_until(data, dataoffset, ':');
				chrs = keyandchrs[0];
				keys = keyandchrs[1];
				dataoffset += chrs + 2;

				for(var i = 0; i < parseInt(keys, 10); i++){
					var kprops = _unserialize(data, dataoffset);
					var kchrs = kprops[1];
					var key = kprops[2];
					dataoffset += kchrs;

					var vprops = _unserialize(data, dataoffset);
					var vchrs = vprops[1];
					var value = vprops[2];
					dataoffset += vchrs;

					readdata[key] = value;
				}

				dataoffset += 1;
				break;
			default:
				error('SyntaxError', 'Unknown / Unhandled data type(s): ' + dtype);
				break;
		}
		return [dtype, dataoffset - offset, typeconvert(readdata)];
	};

	return _unserialize((data + ''), 0)[2];
}